The present invention relates to a method and apparatus for increasing the surface area of insulator bodies.
The insulating properties of insulating bodies are frequently lost or materially reduced because their surfaces become contaminated by conductive deposits. This may be caused by metal vapors, for instance, which are deposited on an insulating body when sparkovers occur or during the operation of metallic-ion sources.
Attempts have been made to improve the insulating properties of insulators by increasing their surface area. To this end, a specialized shaping of the insulating body is used, e.g., the surface area may be increased by means of surface embossments or ribs. The insulating properties are then supposed to worsen only after there has been relatively extensive contamination by conductive deposits on the increased insulator surface.
However, the increase in surface area attainable by such shaping is rather small, i.e., by a factor of 10 or less, so that only limited protective effects are attained.